1. Field of the Invention
The present invention relates to a surface structure of wadded seat which includes a trim cover covering a seat pad and also to a method of manufacturing a surface structure of the wadded seat which includes a trim cover covering a seat pad.
2. Description of the Related Art
A vehicle seat comprises a seat cushion and a seatback, each including a seat frame (a seat cushion frame or a seatback frame) which is a skeleton member, a seat pad (foam member) made of, for example, urethane foam, and a trim cover (surface member) which is composed of a plurality of trim cover pieces sewed together and which is shaped like a bag. The seat pad is mounted on the seat frame, and the trim cover covers the seat pad. The vehicle seat is thereby provided.
A console, which is, like the vehicle seat, an inner component of the vehicle, has its skeleton member covered with a seat pad. The seat pad is covered with a trim cover which is composed of a plurality of trim cover pieces sewed together and which is shaped like a bag.
Trim covers are known well, which excel in cushioning property or decorativeness and may therefore impart a luxurious feel to the vehicle seats or consoles. See, for example, JP 05-018399Y and WO 2006/028206. For instance, a thin wadding member is laid on the back of a trim cover made of, for example, synthetic leather, enhancing the cushioning property of the trim cover. Further, two trim cover pieces may be sewed at abutting ends (hereinafter called “trim cover ends,” as needed), single-stitched or double-stitched, thereby giving the trim cover decorativeness.
JP 05-018399Y discloses a configuration in which thin wadding members are secured to the back of a the trim cover and a plate-like core piece is sewed to the back of the trim cover. The seat pad has, in the surface, a groove that can hold the core piece. Left and right claws are symmetric to each other and extend from the wall of the groove. When the claws are fitted in the groove made in the sheet pad, the wadded trim cover is attached to the seat pad.
WO 2006/028206 discloses a configuration in which two trim cover pieces have a seam allowance (a margin to seam) each, at one end, and in which the trim cover pieces are sewed to each other, leaving the seam allowances. The ends of each seam allowance, i.e., the ends of the trim cover, are folded onto the back of the trim cover. The seam allowance having ends so folded is single-stitched to a plate-like core piece made of resin. If the core piece is not secured on the back of the trim cover, an additional wadding member will be adhered to the back of the trim cover.
The seat pad has, in one surface, a recess that can hold the core piece. The core piece provided on the trim cover is fitted in the recess and adhered to the seat pad.
Patent Literature 1: Japanese Utility Model unexamined Publication JP 05-018399Y
Patent Literature 2: International Publication WO 2006/028206
In the structure disclosed in JP 05-018399Y, the core piece of the trim cover can be firmly fitted in the groove only if the left and right claws are fitted in the groove. However, the use of the core piece increases the number of components required. Further, the core piece is made of hard material so that may not easily disengaged from the claws provided in the groove, unlike the trim cover that is made of soft material such as unwoven cloth. Inevitably, it is not easy to single-stitch the core piece and the trim cover together, which are made of different materials. Further, the single-stitch seam is uneven, lowering the outer appearance of the trim cover. Consequently, the trim cover may fail to have a luxurious feel.
Moreover, a groove must be cut, and a core piece must be fitted in the groove. This inevitably complicates the manufacturing of the trim cover.
In the structure disclosed in WO 2006/028206, the plate-like core piece is fitted in the recess made in the seat pad. The trim cover is therefore firmly secured on the seat pad. Further, the core piece and the seam allowances of trim cover are single-stitched together, improving the decorativeness, i.e., outer appearance, of the trim cover. The core piece is indispensable, however, increasing the number of components required. Still further, the manufacture of the trim cover will be complicated because the core piece is held in the recess with an adhesive agent.
The manufacture of the trim cover is further complicated since the additional wadding member is adhered to those parts of the back of the trim cover, to which core pieces are not secured. Since no wadding member is attached to the core pieces (namely, the core pieces are not backed), any part to which the wadding member is not adhered has no cushioning property. As a result, the occupant sitting on the seat cushion has one feeling at a wadded part and another feeling at a non-wadded part, inevitably feeling not so comfortable.
An object of this invention is to provide a surface structure of wadded seat, which has a good outer appearance and high cushioning property, without increasing the number of components.
Another object of this invention is to provide a method of manufacturing a surface structure of the wadded seat which the manufacture of the trim cover is not complicated.